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- USA
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- USA
- CAN
Ships within 48 hours · Estimated delivery Jul 15 - Jul 20
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Description
Seachem Laboratories Reef Advantage Calcium SupplementReef Advantage Calcium is a non caustic (pH 8. 3 8. 6) optimized blend of ionic calcium designed to restore and maintain calcium to levels found in natural seawater. Calcium and carbonates are essential to all coral growth. If either becomes deficient, coral growth will cease, followed by a rapid decline in coral health. To prevent this you must provide calcium (Reef Advantage Calcium) and carbonates (Reef Builder or Reef Carbonate). Reef Advantage
Reef Advantage Calcium is a non-caustic (pH 8.3-8.6) optimized blend of ionic calcium designed to restore and maintain calcium to levels found in natural seawater. Calcium and carbonates are essential to all coral growth. If either becomes deficient, coral growth will cease, followed by a rapid decline in coral health. To prevent this you must provide calcium (Reef Advantage Calcium) and carbonates (Reef Builder or Reef Carbonate). Reef Advantage Calcium also includes magnesium and strontium in amounts proportionate to typical utilization ratios (100:5:0.1, Ca:Mg:Sr). This allows one to maintain these two important elements while maintaining calcium. Unlike limewater (kalkwasser), Reef Advantage Calcium does not have a caustic pH and will not deplete magnesium. Used as directed, it will not deplete alkalinity. DO NOT OVERDOSE: Excess calcium may enhance the loss of carbonate alkalinity. Do not directly mix with any carbonate supplement. Best if calcium & carbonate additives are added on alternate days or at least 30 minutes apart. Guaranteed Analysis: Calcium (Ca) 34.7%; Magnesium (Mg) 1.73%; Strontium (Sr) 0.0346%Shipping Notes
- Free Standard Shipping on $100+ Orders to the USA.
- Except Preorder products are shipped in 48 hours.
- Delivery to the USA:
- Standard Shipping : 3-10 business days
- If time is of the essence, please consider selecting expedited delivery for faster service.
Exchange/Return Notes
- We offer a 30-day return/exchange service after receiving.
- Final sale items are not eligible for returns or exchanges.
- To process your return/exchange, please contact us at [email protected]
- Please click here for more details>>> Return & Exchange Policy
4.7 ★★★★★
Based on 1387 reviews
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Product Reviews
★★★★★ 5
Finally!
Size: X-Large, Color: All Black D (5-pack)
Finally, comfortable underwear that don’t end up giving me a wedgie. I have a round booty and most cuts of underwear end up shifting as I walk and sit. The hem of the underwear comes right under my cheeks and the lightweight material ensures there’s no panty line and no shifting to where I don’t want them! I’m definitely purchasing more.
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Reviewed in the United States on May 17, 2026
★★★★★ 3
Ehh
Size: Medium, Color: Multicoloured E-(5-pack)
Very thin, still comfy but very thin material. Super soft though. I've worn and washed and they have held up but I won't be repurchasing bc these are so thin
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Reviewed in the United States on April 14, 2026
★★★★★ 5
They’re fantastic!!!!
Size: X-Large, Color: Multicoloured E-(5-pack)
My clothing size is 16/18 and XL. Even though Amazon suggested a size XXL, I ordered my normal XL and they fit perfectly.
The fabric for this style is 92% bamboo viscose and is amazingly soft and almost silky feeling. I had ordered a different boy short in this brand but they were 80% bamboo viscose and the fabric was significantly heavier. I returned those and ordered these.
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Reviewed in the United States on April 25, 2026
★★★★★ 5
Flattering fit
Color: White, Size: Large
Flattering fit and comfortable. Material is a bit see through but that doesn't bother me. Great value for a nice looking shirt.
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Reviewed in the United States on May 28, 2026
★★★★★ 4
Super Soft and Comfortable, Just Not the Most Forgiving Fit
Color: Purple, Size: X-Large
This top is incredibly soft and comfortable, which was the first thing I noticed. It has a really nice, lightweight feel that is easy to wear and not too thick or heavy, making it great for everyday use. Fit is true to size, but I would not call it very forgiving through the midsection. It is not cropped, but it also does not have much added length, so it hits in a way that can highlight the stomach area more than expected. Just something to be aware of depending on how you like your tops to fit. I know the material blend can pricey but still not sure I would say it's value is worth it. I like it, but I odn't love it. The purple color is better in person than the picture though! Overall, it is a great basic if you are looking for something soft and comfortable, just know it leans a bit more fitted than flowy.
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Reviewed in the United States on March 26, 2026